1. Field of the Invention
This invention relates to an interrupt system and more particularly to an interrupt system that indicates an interrupt by writing to a memory associated with the device to be interrupted and then scanning that memory.
2. Description of the Prior Art
Multiple central processing units are used in sophisticated computer systems to increase throughput and reliability. A major design problem which must be solved in any such system is interrupt management. Interrupts are external events which occur and require attention by a central processing unit.
A common prior art system for managing interrupts is one in which one of the central processing units is assigned to handle all interrupts. Special interrupt conductors interconnect the interrupting device with the one central processing unit.
Another prior art system provides a set of interrupt wires, each set connected to one of the central processing units. This allows interrupting devices to interrupt the processor designated. In these systems, there is ordinarily a separate mechanism on the interrupting devices which perform the interrupt function including the arbitration of interrupts from interrupting devices which may signal simultaneously.